The invention pertains to self-sealing valved fluid couplings of the pivotal valve element type.
Self-sealing valved fluid couplings utilizing valve elements which automatically open upon connection of the coupling halves, and close upon coupling halves disengagement, are widely used in hydraulic systems and, in particular, hydraulic systems utilizing flexible hose lines. The valve elements of such couplings may constitute poppets, sleeves, spools, and pivotally mounted valves. One of the serious disadvantages of most self-sealing couplings lies in the high flow resistance produced due to the fact that the majority of self-sealing coupling constructions support the valve elements at the center of the flow passage requiring that the fluid flow through spiders and orifices when the valve is open, resulting in fluid flow resistance and pressure and capacity losses.
Those self-sealing fluid couplings producing minimum pressure loss during flow usually utilize pivotally mounted valve elements, such as shown in U.S. Pat. Nos. 586,618; 2,956,582 and 3,127,148. Such patents disclose fluid couplings having pivoted valve elements adapted to be engaged by an element during coupling and the valve elements pivot to an open position substantially removed from the flow path. However, such constructions often still produce slight restriction of the flow passage and, in the past, the valve elements were not of such configuration as to permit high capacities to be handled through the coupling and yet maintain the exterior diameter of the coupling to a size only slightly larger than the associated conduit, such as hose line.
Improved flow characteristics of pivoted valve elements have been achieved by shaping the cross-sectional configuration of the valve elements to substantially correspond to the transverse cross-sectional configuration of the flow passage. However, prior art devices have compromised the valve configuration in order to achieve acceptable flow characteristics and a desired sealing arrangement between the valve elements and, thus, flow passage restrictions often still occur through such couplings.
Also, while many self-sealing fluid couplings utilize locking ball detents and actuating sleeves to hold the coupling halves interconnected, such locking sleeves utilize an axial displacement upon the coupling for movement between coupled and uncoupled conditions. Thus, when the coupling is utilized with a hand-carried accessory, such as a nozzle or attachment fitting, it is possible to inadvertently displace the locking sleeve and prior art devices do not have effective safety arrangements to prevent such accidental actuation of the coupling latch structure.